Powes hammer



June 30, 1931. J. H. GREENLEY POWER HAMMER Filed June 12, 1929 3 Sheets-Sheet l gnaw-tor, JAY. H. GREfINhtY Julie 30, 1931. J EY 1,812,650

POWER HAMMER Filed June 12, 1929 5 Sheets-Sheet 2 June 30, 1931. RE L Y 1,812,650

POWER HAMMER Filed June 12, 1929 a Sheets-Sheet s 1 gwuentov JAY H. GREENLEY Patented June 30, 1931 PATENT OFFICE JAY HIE-AM car entry, or BUFFALO, New YORK rowan HAMMER Application filed June 12, 1929. Serial No. 370,357,

My invention relates to power hammers and especially to such hammers designed to furnish a light sharp stroke in a direction not necessarily limited to a. single direction 5 "in the axis of the mechanism.

There has developed in the last few years a demand for tools and machines for use in securing metal strips of various shapes along the edges of base material, and has often 1.0 been done by nailing or riveting the strip to the base, following the driving operation by suitable means of smoothing over the head of the fastening means, such as the nail head, or otherwise avoiding'the rough and inartistic appearance of the strip surface and indeed, to wholly obscure the appearance of the fastener, if possible.

One of such demands 'hasbeen that for installing metal mouldings upon automobile "bodies, such mouldings being usually formed as a continuous strip fro-m one of the softer metals, certain aluminum compositions being found well adapted for the purpose. Such mouldings are provided with spaced apertures after moulding,.b-ut usually before the operation of securing the strip to the auto bo'dv.

It is an object of my invention to provide a portable power hammer actuated through driving connections from the power source,

which connections shall be more or less flexible to permit moving the hammer from one point to a'nother,=as where it may be desired to smooth over the head of a fastening means,

as above explained; Various power may be used, such as electric or pneumatic; The device I shall here disclose may be readily carried by an operator while retaining actu- 7 ating connection as stated.

Heretofore, it has been usual to drive the head of fastening means, such as nails, by strokes from a single hammer member, and in some cases to usethe same tool to batter down the moulding material into the aperture above the nail head, and the device has been ordinarily effective for the purpose when the moulding was of a very simple form with flat outer surface. though the power for the tool has usually been manual with its consequent disadvantage. It is a special obdrill or similar rotatin member at the other 9 C:

ject of my invention to provide'a power hamthe base of the strip. The use of single axial'ly operated hammers for drip moulding is f quite inefiective, since the flange is apt to be scarred or otherwise injured by the strokes of the hammer. The use of my clustered hammers serves to quite fully avoid such difficulty.

It is a further object of my invention to provide, either with or without other hammer members, a hammer member provided with a toe member at its striking enc secured thereto, preferablyintegral therewith, for driving toward the surface of the moulding, but beneath the flangethereof, provided the drip moulding is used, and is to be applied to the base material, the toe member serving the purpose of fastening when the straight line extending upwardly from the fastening,

would be apt to collide with the edge of the flange.

Inytools for this purpose, there is more than an ordinary relation existing betwecir the means for drilling out the apertures in the material, in this case the moulding, and thehammers for thereafter smoothing over the'surface of the moulding above the heads of the fastenings. It is therefore, a very important object of my invention to provide my portable tool herein disclosed, as compound, having a common axis with the stated power hammer structure at one end thereof, and a end,ai1 intermediate motor serving for driving'the axial parts of either or both.

"With the above and other objects in View theiinventionresides in the combination and arrangement of parts as hereinafter setforth,

shown, described and claimed, and illustrated in the accompanying drawings, in wl1ich- Figure 1 is a side view of the mechanism in position for calking, the hammer mechanism'being shown in section in a plane indicated by the broken line 11 of Fig. 2, and other portions shown in elevation;

Figure 2 is a transverse section taken on the line 22 of F ig. 1;

Figure 3 is a side elevation of the wabbler;

Figure l is a transverse section in the plane indicated by the line l& of Fig. 1;

Figure 5 is a transverse section on the line 55 of Fig. 1;

Figure (5 is a diagrammatic view of the connections for the motor and a proposed arrangement of the switch;

Figure 7 is a cross sectional view of' drip moulding showing an aperture to receive the fastening;

Figure 8 is a similar view showing a fastening secured in the aperture;

Figure 9 is a side elevation of a modified form of means for actuating the hammer members from the motor;

Figure 10 is a central longitudinal section taken on the line 10-10 of Fig. 9;

Figures 11 and 12 are side elevations of the cam member shown in different positions of rotation;

Figure 13 is a sectional detail on the plane indicated by 13-13 of Fig. 10, and

Figure 14 is a sectional detail on the line 14 14t of Fig. 10.

Referring more particularly to the drawings the numeral 5 designates a portable tool generally, carrying a hammer mounting (i at one end thereof, and a drill 7 at the opposite end of a common axis, both being driven by an i ntern'iediate motor 8, and the whole supported upon a handle 9, here illustrated as guiding the electrical connections 10 from an electrical motor to a suitable source of current.

The general form of the hammer mounting is that of the frustum of a cone. as shown in Figs. 1, 9 and 10 carrying reciprocating hammer members 19 and 20. upon the periphery of the mounting 6, and directed toward a common point, such as a nail head 17 where the force is to be applied.

lVhen drip moulding 12 is to be applied to a base material 15, an overhanging flange 13 almost shelters an aperture 11 intended to receive the fastening 16 which is here shown as a. nail whose head 17 is to be concealed in the metal of the moulding. The lower surface 1 1 of the moulding 12 may be slightly concave, as shown in Figs. 7 and 8, but which will be rendered more or less flat after the fastenings have been applied, as shown in Fig. 1. The flange 13 forms a clear space 18 underneath it in which one of the hammers may operate, as will be later explained.

The motor 8 is intended to be quite conventional in its character, no patentable merit being claimed for it per se. Its armature is however mounted for rotation on a common axis with the drill 7 and the frusto-conical mounting 6. The entire outer frame of the tool 5, including the mounting 6 and the hammer members 19 and 20 carried thereon, are non-rotatable, the motor armature rotating therein and driving the main shaft which, in the form shown in Figs. 1 and 2, drives the drill 7 at one end and the ratchet gear 25 at the other.

The member 6 has extended on its outer surface spaced ridges 24 upon the larger end, as shown in Figs. 1 and 2, each of said extensions having channels 22 lengthwise thereof to guide the hammer members 19 and 20 in their reciprocation. The outer surfaces of these extensions 24 are provided with detachable metal covers 26 to hold the hammer members in the channels 22. Between the ridge members 24: the periphery of the mounting 6 provides a hollow metal shell 23 within which actuating means for the hammers may be operated. At the smaller end of the mounting 6, as shown in Figs. 1 and 2, a centrally-apertu red closure member 27 is mounted integral with the walls of the frustum. This aperture 28 is axial of the member 27 and receives therein a stem 29.

The stem 29 has a threaded lower end 31 extending beyond the lower surface of the closure member 27, and receives thereon a locking nut 32 to hold the stem in its lowermost position. The opposite end of the aperture 28 is enlarged at 33 to receive an enlarged portion 34 of the stem 29, and thereby prevent too far lengthwise movement of the stem in the closure 27. Somewhat spaced from the enlargement 34 the stem 29 has secured thereon an enlarged ball 35 uponwhich the wabbler member 36 is movably mounted, as will be later explained more in detail.

The wabbler 36 is a quite irregular shaped actuating member comprising a solid cylindrical stem 37 having a short reduced end 38 for driving and an enlarged socket portion 39 at the opposite end. This portion has a peripheral portion 40 connecting with the stem 37 by a hollow cup-like, smaller portion 11 which is formed of proper size and shape to receive the ball or sphere 35 neatly, so that the \vabbler 36 may well be swung about this ball as a fulcrum. On the inner surface of the portion 10 are secured the bent ends 42 of widely spaced, flat plates 13 whose opposite ends are operatively connected with the ham mer members. The inner but bent ends 42 are inserted in small notches 14C of the said peripheral portion 10, to secure the said plates 43 against twisting movement. To look all or these plates 43 in the portion 40 an annular locking member &5 having a suit able central opening to properly engage the ball "withouttoo serious bindin secu'redto the portion 40 by suitable fastening members such as screws 46, to assist in securing the plates-43 to the wabbler 36.

The outerends-of the plates 43- will be rather loosely engaged in inner notches 47 t of the hammer members, so that swinging movement-of the wabbler 36 upon the ball 35 will reciprocatethe hammer members in their channels 22.

In the-formshown in Figs. 1 to 4 inclusive, a disc shaped actuator 48 is mountedfor axial rotation within the mounting memher 6 in suitable bearings 49, as shown in Figl 1. On the face of the actuator toward the'motor, is provided a peripheral flange 50 forming a cylindrical pocket 51 receiving axiallythereof the ratchet gear 25 which is keyed to the end of the shaft 30. The size of the gear 25 permits mounting in the space between it and the flange 50, one or more pawls 52-pivoted loosely upon pins carried by the actuator 48, and normally pressed intoengagementwith the teeth of the gear by springs 53 outside the pawls. Rotation of the rotate) which reciprocatesthe hammer mem-- bers in regularsuccession. Two of-the actuating plates 43 operate the two hammer members 19 each of which has a reduced toe portion 55 for delivering'their strokes. The other "plate 43 however, reciprocates'an actuating bar 21 which moves in a similar channel 22 but does not deliver its stroke directly tothe common" pointwith the hammers 19, but delivers its stroke to the bent foot 56 of a hammer member 20 whose main portion moves just outside the member 21, as shown in Fig. 1, the metal covers 26 for these parts 20 and 21 being correspondingly shaped to protect both the latter elements by having a. shoulder 57to limit the inward movement of the hammer 20.

The: oifset foot 56 of the hammer 20 has a bent toe portion 58 which is especially designed for operation in the space 18 beneath the flange 13of drip moulding, and is thus well adapted for driving a nail head or thematerial for covering the nail head. Because of the peculiar position which the parts 56 and 58 must take in their 'drivingaction, it

will be" advantageous to deliver the strokes of the reciprocating bar 21 thus indirectly,

rather:thandirectlyfas the toes'55 carried-by the hammers19- do; It is to, be% understood action, is r that the toes 55 and 58 would be very closely, adJacent eaclrother in a clustered po'sit-ion,%

7 if the strokesof the threehammers 'were delivered-at one time. They do not however, operate at the same =moment because of "the" action of the wab-bler element 36 which posi tively controlsthe successionof the three hammers in a definite order, so-th'atbut one toe will strike the area of delivery ata given 1 moment, one rotation of actuator 48*cau'si 'ng one stroke each of the three hammers at separate times.

The end of the shaft 30 opposite'the actuator"48,will be providedwith suitable split fingers 59 externally threaded to receive an adjustment nut 60' to tighten a rotating tool within such fingers, some formof bit or drill 61 being shown mounted for operation. Upon the face of an end cap 62 havinga large cen- I tral aperture through which the shaft 30 projects, a series of spaced rods 63 are mounted in apertures 64 to provide for mounting a protecting sleeve 65' having apertured external ears 66 which are rigidly secured upon the rods 63, as by a suitable threaded connection 67. The inner ends of the rods 63' are provided with enlarged heads '68 to prevent outward movement, and e ach'rod-is provided with a coil spring 69 surrounding it and serving by compression to hold therods and sleeve 65 carried thereby, in their extreme outward position, as shown in Figs. 1 and 10; Nor mally, the outer edge of the'sleeve will be slightly beyond the end of the'prote'cted tool;

The innermost position of one of the rods 63 is shown in dottedlinesin Fig- 10, in which position the springs 69 will obviously be compressed between the wall of the cap' 62 and the ears 66 of the sleeve. VVlientherefore,- theoperator desirest'ouse th'e'tool 'l, he will force the sleeve 65 against-the mate'- rial and about a pointat whic h'the tool will operate, and manually'overcometheforceof the springs and bring the t'ool 7 into positive contact with the material tofbeacte'd upon, and when such pressure force is re-" leased, the sleeve will remain in'contact while the tool is relatively withdrax'vn': g

In Figs. 9 to 1-2 inclusiveyl' have shown a slight modification of the mechanismfor actuating the hammer members from the 'mo tor shaft 30, though not'changing the opera' tion of the tool 7 at the opposite'end of the shaft, nor modifying the mounting of the mot-or 8 in the generalmechanism 5. In this modified form, I substitute a revolving cam member for the wabblcr 36 of the first form, and make-the mechanical changesuiecessitated by such substitution; In this modi fied form, themounting' member76will be rigidly connected with themain part of the tool 5, the shaft 30 and parts driven by it rota-ting withinflthis m'em'berflVithjinth-f largerend of the latter'a fianged disc T1 is I mounted detachably by screw engagement at 72, and a closure member 73 is secured within the smaller end and is provided with a bearing socket on its inner face to receive the extreme end of the shaft extension 74 whose inner end is operatively engaged with the shaft 30 by a pawl and ratchet engagement in much the same manner as that inclicated in Fig. 4, though in this form the drive shaft will carry the peripherally flanged disc 75 carrying on its inner face the pawls 77 which are spring pressed inwardly into engagement with the ratchet gear 78 which is mounted on said shaft extension 74, the latter rotating in bearings in a central aperture of the disc 71.

The outer end of the shaft extension 74 is supported within the socket 79 of the member 7 3 by a suitable roller bearing 80, as shown in Fig. 10. The cam member receives the shaft extension 74 through its axial center 81, and the said extension is keyed or otherwise secured non-rotatably to the said cam. The gear 7 8 is pinned to such extension, as is also the hub 82 of the usual fan 83. The cam member 70 is frusto-conical in general shape and has an external cam groove 84 provided by parallel ridges 85 which receive between them the cam rollers 86 each of which is mounted for rotation upon a. pin projecting inward from the members 19 and 21. The ridges 85 are of such form that the cam groove 84 will have a gradual incline portion 87, an abrupt inclined portion 88 and an intermediate portion 89 substantially at right angles to the axis of the cam member 70. The result will be a gradual rise of the several members 19 and 21 in proper succession, and the delivery of a sharp sudden stroke by the toes 55 and 58 of the members 19 and 20, upon each rotation of the shaft 74 and cam member 70.

In Fig. 11 is shown the more abrupt incline portion of the cam, and in Fig. 12 the more gradual incline portion is seen. The complete cycle therefore, of a rotation of the extension comprises a gradual withdrawal of the hammer member 19 or 21 by the actuation of the roller 86, followed by an interval of inactix e condition of such parts as the roller 86 travels in the intermediate portion 89 of the groove 84-, after w] 'ch the roller and its member 19 or 21 is thrust sharply and suddenly toward the area above the head of the fastener, after which the gradual rise therefrom of a new cycle follows in succession, the strokes of the other hammers being delivered while the other two are under the control of the intermediate cam portion 89, or as one of them is about to enter such portion from the gradual incline 87.

The sections shown in Figs. 1 and 10 show the plunger 21 as it has just delivered its stroke upon the foot 56 of the hammer mem ber 20 having the toe 58 which is shown in these views as having just received the impulse from the reciprocating plunger 21. This actuation of the bar 20 and the parts 56 and 58 carried thereby will result in similar hammering of the nail head 17 or the mould ing material just above it, as shown in Fig. 8, whether such member 20 is actuated by the plates 43 carried by the wabbler 36, or by the cam rollers 86 driven by the cam 70 which is rotated directly by the shaft extension 7 4. In either construction, the hammer members 19 are reciprocated to cause their end portions 55 to strike the desired area, or the plunger 20 is driven upon the same approximate area by the reciprocation of the actuating plunger 21. In either case the driving of the three hammer toes 55 and 58 upon the clustered area shown in Fig. 5, is accomplished by the rotation of the main shaft 30 by the motor 8.

My improved mechanism has special advantages in delivering a plurality of hammer strokes upon a fastener such as a nail head 17, or in battering down the outer metal 90 over the head of such fastener as indicated in Fig. 8. My mechanism is also peculiarly effective in delivering such plural strokes upon a fastener for moulding having the over-hanging flange 13, known as the drip moulding; but my mechanism is not at all limited to such driving operations upon flanged moulding, as will be obvious, since the absence of the flange 13 in no way modifies the character of actuation of the hammer members or the character of the function desired by the toe parts 55 and 58. My compound hammer is just as positive in its action and effective in operation when used upon the simple or flat strip of moulding as it is when used for securing or smoothing the surface of the flanged moulding. The closely associated points of delivery of these toe parts by the hammering members in proper succession is a remarkable feature of the operation in either case.

In the use of the tool on the end of the shaft 30 opposite the composite hammer, the said shaft will be rotated in an opposite direction from that in which it is driven to actuate the hammer. The control of the motor 8 is effected by manual operation of a switch which, for convenience is abar 91 movable in the direction of its length, but transverse of the handle 9, so that the said bar may be given the desired impulse by the thumb or a finger of the hand which may at the time support the handle 9. I have shown the position of this switch bar 91 in Fig. 10, and a diagrammatic showing of the contacts effected by actuating the bar, in Fig. 6'.

As shown in the latter view, the bar 91 is in neutral position. Movement of the bar to the right in Fig. 6, will make contact between the points 92 and 93 and the points 94 and 95, respectively, while reverse movement of the switch 91 will make such contact with the points 96 and 97, thus reversingthe direction of current in the field and thereby the rotation of the motor. To avoid unintended release of the switch bar and consequent possible'rotation ofthe tool 7 when the sleeve 65 is in i its normal outward position, asshown in Fig.

. inward movement of such rod will strike the beveled surface 98 of a radially slidable rod 99 and move the latter outward, as indicated .in Fig. 10, to release the pin 100 carried by the rodfrom a notch 101 in the switch bar 91, andpermit the endwise movement of the bar. to operate the switch and thereby reverse the direction of current in the field and-thereby reverse the rotation of the shaft and the tool 7 carried thereby. Such actuation of the tool 7 will continue until the sleeve- 65 is forced outward by the springs 69. The pin 100 carried-by the rod 99 will follow the outline of the bar 91 and will enter the notch 101 by the normal impulse of a suitablespring-(not shown). It will thus be seen that when the rod 99 rises to its extreme in- 1 ner position,

it will lock the rod 63 in its innermostposition by contact with its head 68.

Obviously, the armature circuit is not re-v 1 versed.

Another portion ofthe bar 91 may be provided with a series of notches 102 for receiving a pivoted latch 108 whose contact point t 104 will be normally held in engagement with one of saidnotches by means of the spring.

105, so that thebar 91 is normally restrained longitudinally from returning to a position in which the pin 100 is forced out of the rod 63. In the position shown in Fig. 10, a movement of the bar 91 to the left will, by

= the direction of rotation of the motor shaft -30, and latch it in such extreme positlon by means of the latch 103. The switch bar 91 notch-101 and the rod 99 would release the the contacts made as shown in Fig. 6, reverse will remain in such position until the latch 103 is disengaged.

"The operation of the mechanism is as follows A continuous strip of moulding which may be of the general form shown in Figs. 5, 7, 8

and 10, or-which may be of the simplerdesign,-andpossibly wholly lacking the overhanging flange 13, but provided with the apertures 11 for receiving the fastenings therethrough, having been positioned upon the casing to which it is to be secured, and the fastening 16'having been driven through the apertures therefor and temporarlly secured in position the operator now grasps my portable tool by engaging the handle 9 thereof by his fingers, carrying the hammering cone 6=on a'level above that of hishand, and rests the toe 58 of thehammering member 20 upon the'head 17 of the fasteningna-il 16, preparatory'to starting the mechanicaloperation of the hammer members 19 and 21, upon closing the circuit by shifting the switch bar 91. Suitable elongated flexible connections-10 are provided to enable the operator to apply the tool at points widely divergent.

The toe 58 of the hammer member 20 serveswell to guide the operator in positioning the too-l directly over the nail head 17.

When the switchbar 91 has been shifted to close the circuit to drive the motor 8' and thereby the main shaft 30, the hammer members 19 and 21 will be reciprocated successively by the rotation of the disc 48 and thereby the peculiar wabbling movement of the member 36 upon the ball 35, or by the rotation of the cam block and consequent reciprocation of the hammers. In either case, the successive action of the three members 19 and 21, as indicated clearly in Fig. 2, will be maintained, the toes 55 and 58 delivering an" light contacton that surface, as the member- 21 delivers its stroke upon the foot 56 ofthe hammer member 20 intermediate the blows delivered by the toes 55. Y

The three toes 55 and 58 serve as hammer heads which may be delivered successively upon the head 17 of a fastener 16, and may serve equally well, when the nail head has been sunk in the opening 11, to press the metal edges 90 over the head 17 and thus produce a smooth surface over the fastener, in the manner shown in Fig. 8. In Fig. 7;, the metal 90 is shown before the fastenerhas been positioned in the moulding. My tool therefore serves two purposes, that of driving the fastener 16 into tight contact, and

that of smoothing the moulding material over the fastener head,

The operator having delivered the hammer blows of one end of the tool'to aseries of fasteners and moulding material upon it, he may now shift the switch bar 91 to cease the rotation of the actuating disc 48 or of the tool 7 operatespreparatory to the hammering operation of the opposite end of the common axis of the compound toola'ctuated by the common motor 8. However,the tool 7 is not restricted to a drill, but may be any rotatable tool such as a screw driver or any other rotatable member fitting the socket ordinarily adapted to receive the drill.

It is an especial advantage of my hammer mechanism that a plurality of hammer members operate upon a common surface area, striking the area while the several hammers are closey adjacent, though each slightly inclined to such surface. This use of adjacent hammers for striking a small surface area, such as a nail head or a metal surface imme diately above such nail head, has a decided advantage in requiring little force of each hammer member, while the rapid actuation of the several members on an approximately unitary surface, delivers a strong force by their successive operation. This fact is of great importance when such unitary area is so limited as a nail head surface.

The rapid operation of the several hammers upon areas so closely adjacent is so advantageous especially when the strokes must be delivered upon a surface so close to the edge of an overhanging flange, such as the part 13 of drip moulding, and a further greatadvantage results from the under-bent toe 58 from the member 20, especially when the stroke is to be delivered from a source above said flange 13. While I have disclosed my compound hammer mechanism as comprising three reciprocating hammer members, it is by no means essential that themechanism should be restricted to this number, but such associated members result in the advantages mentioned when so few as two hammers are mounted in inclined position.

It will be readily apparent that a greater number than three hammer members may be mounted in a general conical formation, and the operation of the several hammers may be in succession, as in the manner above explained when two or three hammers are operated together. It will be clear also that each rotation of the member 48 or the member 70, will deliver as many strokes as there are hammers so associated together. The number of said strokes for each rotation of the cam member may be widely varied by the number of waves in the cam groove 84 upon each rotation of the cam. In any case. the operation of the mechanism will result in a rapid series of short strokes which renders it very practicable to hold the tool in very positive position over the nail head.

Having thus described my invention, what I claim as new and desire to secure by United States Letters Patent is:

1. A portable compound tool comp-rising a power shaft, a plural hammer mechanism mounted upon one end of said shaft, means for successively impelling the hammers in converging lines to a common area, and flexible connections between a source of power energy and said power shaft to actuate the latter.

2. A portable compound tool comprising a power shaft, a plural hammer mechanism mounted upon one end of said shaft, means for successively impelling the hammers in converging lines to a common area, a motor mounted co-axially with said shaft, a sup-' porting handle upon which the shaft and connected parts are mounted at right angles thereto, and means flexibly connected with a source of tor.

3. A compound tool comprising an elongated power shaft, a motor mounted coaxially with said shaft, a supporting handle for said tool, a plural hammer mechanism mounted at one end of said shaft, means for successively impelling the hammers in converging lines to a common area, a motor mechanically connected with said hammer mechanism, flexible means carried by said handle for connecting the said motor with a source of power energy, and means mounted upon said handle for manual operation to control the hammer mechanism.

4. A power hammer mechanism comprising a motor and connections between said motor and a source of power energy, a series of power hammers mounted for delivering strokes successively in converging lines upon a common area, a supporting handle upon which the motor and connected parts are mounted, the axis of the handle being at right angles to the axis of the motor.

5. A power hammer mechanism comprising a motor and flexible connections between said motor and a source of power energy, a seriesof power hammers mounted about a common axis for delivering strokes in convergent directions upon clustered areas, and mechanical connections between the motor and said hammers to reciprocate the latter in proper I succession.

6. A power hammer mechanism mounted upon a suitable handle and comprising a motor and connections between said motor and a source of power energ a series of power hammers mounted about a conmaon axis for delivering strokes in convergent directions upon clustered areas in a direction axial of the motor, and mechanical connections between the motor and said hammers to reciprocate the latter in proper succession. 7 A power hammer mechanism comprislng a motor, a motor shaft and connections between said motor and a source of power energy, a series of power hammers mounted on said shaft for delivering strokes in convergent directions upon clustered areas successively, and mechanical connections between the shaft and said hammers whereby rotation of the shaft will reciprocate the hammers independently and in proper succession.

8. A power hammer mechanism comprising a motor and connections between said motor and a source of power energy, a series of power hammers mounted for reciprocation power energy for driving said moabout a common axis for delivering strokes in convergent directions upon clustered areas, a common supporting handle being at right angles to the motor axis, and mechanical connections between the motor and said hammers to reciprocate the latter in proper succession.

9. A power hammer mechanism mounted upon a suitable handle and comprising a motor, a series of power hammers mounted for independent reciprocation along converging lines toward a common area, flexible connections upon said handle between said motor and a source of power energy, mechanical connections between the motor and said hammers to actuate the latter successively, and means mounted upon said handle for manual operation to control the reciprocation of the hammers.

10. A power hammer mechanism comprising a rotatable shaft mounted at right angles to a sup-porting handle for said mechanism, there being a channelled cone mechanism at one end of said shaft, hammer members mounted in said channels for reciprocation toward and from a common area, a motor having an axis common with said shaft and driving connections therewith, driving means mounted on said shaft for reciprocating the hammer members in said channels, flexible means carried by said handle for connecting the said motor with a source of power energy, and means on said supporting handle normally operable by a member of the operators hand for shaft.

In witness whereof, I have hereunto set my hand this 4th day of May, A. D. 1929.

JAY HIRAM GREENLEY.

controlling the rotation of said all 

